// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_BROWSER_MESSAGE_PORT_MESSAGE_FILTER_H_
#define CONTENT_BROWSER_MESSAGE_PORT_MESSAGE_FILTER_H_

#include "base/callback.h"
#include "base/macros.h"
#include "content/common/content_export.h"
#include "content/public/browser/browser_message_filter.h"
#include "content/public/browser/message_port_delegate.h"

// Windows headers will redefine SendMessage.
#ifdef SendMessage
#undef SendMessage
#endif

struct FrameMsg_PostMessage_Params;

namespace content {

// Filter for MessagePort related IPC messages (creating and destroying a
// MessagePort, sending a message via a MessagePort etc).
class CONTENT_EXPORT MessagePortMessageFilter
    : public MessagePortDelegate,
      public BrowserMessageFilter {
public:
    typedef base::Callback<int(void)> NextRoutingIDCallback;

    // |next_routing_id| is owned by this object.  It can be used up until
    // OnChannelClosing.
    explicit MessagePortMessageFilter(const NextRoutingIDCallback& callback);

    // BrowserMessageFilter implementation.
    void OnChannelClosing() override;
    bool OnMessageReceived(const IPC::Message& message) override;
    void OnDestruct() const override;

    int GetNextRoutingID();

    // MessagePortDelegate implementation.
    void SendMessage(
        int route_id,
        const base::string16& message,
        const std::vector<int>& sent_message_ports) override;
    void SendMessagesAreQueued(int route_id) override;

    // Updates message ports registered for |message_ports| and returns
    // new routing IDs for the updated ports via |new_routing_ids|.
    void UpdateMessagePortsWithNewRoutes(
        const std::vector<int>& message_ports,
        std::vector<int>* new_routing_ids);

    void RouteMessageEventWithMessagePorts(
        int routing_id,
        const FrameMsg_PostMessage_Params& params);

protected:
    // This is protected, so we can define sub classes for testing.
    ~MessagePortMessageFilter() override;

private:
    friend class BrowserThread;
    friend class base::DeleteHelper<MessagePortMessageFilter>;

    // Message handlers.
    void OnCreateMessagePort(int* route_id, int* message_port_id);

    // This is guaranteed to be valid until OnChannelClosing is invoked, and it's
    // not used after.
    NextRoutingIDCallback next_routing_id_;

    DISALLOW_IMPLICIT_CONSTRUCTORS(MessagePortMessageFilter);
};

} // namespace content

#endif // CONTENT_BROWSER_MESSAGE_PORT_MESSAGE_FILTER_H_
